Rotary Stencils – SPGPrints RotaMesh® & Gallus Screeny

Rotary ‘silk’ screen printing

The only process that guarantees opaque ink coverage. Historically limited to low runs as a flat bed process, technologies developed by SPGPrints and Gallus have enabled screen printing to be included on the flexographic line. Speciality inks, tactile varnishes and opaque colours can be included to enhance product and packaging decoration.

Irrespective of which system you may need, MPH has invested into prepress technologies for both systems in order to provide UK flexographic printers with a fast, reliable service as well as high resolution flexographic printing plates guaranteed to register perfectly.

SPGPrints RotaMesh®

Much like a traditional silk screen, SPGPrints RotaMesh® system can cover several job runs with the unique ability to be washed out and re-imaged over and over again. RotaMesh® screen is a non-woven, electroformed mesh made out of 100% nickel. The hexagonal, honeycomb structure enables extremely sharp printing with maximum stability and consistency. RotaMesh® screens are available in a wide range of mesh counts to meet all application requirements.

Depending on your press, RSI® units may be fitted in a fixed position or on a cassette frame. For optimal flexibility, RSI® can be mounted on a SPGPrints’ Flexible Positioning System. This patented solution allows you to move the RSI® module to any print station in your press.

Want to print even wider and/or longer? Then the RSI® Mid Web print module is your best bet. With print widths ranging from 600 to 900 mm or even wider upon request. Also available in explosion proof execution.

spgprints.com

Please contact us for more details on how this technology can benefit you.

Gallus Screeny

An alternative to Rotamesh® is the Gallus Screeny mesh. Much the same as SPGprints system, a variety of mesh grades are available depending on what is required to be applied to the line.

For its rotary screen modules, Gallus offers Screeny mesh, a nickel-plated stainless-steel fabric that is used to form Rotascreen printing cylinders. The fabric comes precoated with a photopolymer emulsion and a protective film, and it is offered by the meter in rolls or in sheets. Gallus offers eight standard types of Screeny printing plates, which vary from coarse meshes with approximately 64 openings per linear inch (ideal for Braille-printing applications) to fine fabrics with as many as 400 openings per linear in. (designed for halftone and fine-detail work).
Turning the Screeny mesh from a flat printing plate into a Rotascreen complete with imaged stencil is similar to making screens for flatbed screen printing. First, the film is punched with register holes. Then, the Screeny mesh is cut to the required printing length and punched with register holes that correspond to those in the film. Next, the protective foil over the emulsion is removed and the film positive is positioned by means of register pins. The mesh is exposed while flat under high vacuum to ensure that stencil captures even the finest image elements. Next, the photopolymer stencil is developed with a powerful water jet. Brief drying with hot air is required before continuing.
To create a cylinder form, the ends of the printing plate are connected with a plastic sealing device that is locked by means of heat. End caps, called stencil rings (Figure 4), are then attached to create a stable cylinder. The stencil rings also make it possible to connect the finished screens to the drive unit of the printing press. After printing, the Rotascreen ink is cleaned from the screen cylinders using a special automated screen-cleaning device. If the screens are no longer needed, the stencil rings are removed from the printing cylinders. The rings can be re-used for another job, but the mesh cannot be reclaimed–a new Rotascreen is created for every new job.